Alteration of dopamine synthesis in rat striatum subsequent to selective type A monoamine oxidase inhibition.
Pretreatment of rat striatal slices with the selective type A monoamine oxidase (MAO) inhibitor clorgyline was found to produce significant inhibition of dopamine (DA) synthesis. DA synthesis was reduced by nearly 50%, but not until more than 90% of the type A enzyme was inhibited. In contrast, complete inhibition of the type B MAO following deprenyl treatment had no effect. It is suggested that interneuronal accumulation of DA following inhibition of type A MAO leads to feedback inhibition at the rate-limiting step in DA biosynthesis, tyrosine hydroxylation. These results are also consistent with the presence of a type A MAO within DA-containing neurons and provide evidence of a regulatory role for type A MAO in the synthesis of brain DA.
D000818:Animals; D003010:Clorgyline / Q000494:pharmacology*; D003342:Corpus Striatum / Q000378:metabolism*; D004298:Dopamine / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D005246:Feedback; D007700:Kinetics; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology*; D010627:Phenethylamines / Q000494:pharmacology*; D011437:Propylamines / Q000494:pharmacology*; D051381:Rats; D012642:Selegiline / Q000494:pharmacology*
D008996:Monoamine Oxidase Inhibitors; D010627:Phenethylamines; D011437:Propylamines; D012642:Selegiline; D008995:Monoamine Oxidase; D003010:Clorgyline; D004298:Dopamine